function setCookie(name,value,hours,path){  
    var name = escape(name);  
    var value = escape(value);  
    var expires = new Date();  
    expires.setTime(expires.getTime() + hours*3600000);  
    path = path == "" ? "" : ";path=" + path;  
    _expires = (typeof hours) == "string" ? "" : ";expires=" + expires.toUTCString();  
    document.cookie = name + "=" + value + _expires + path;  
}  
//获取cookie值  
function getCookieValue(name){  
    var name = escape(name);  
    //读cookie属性，这将返回文档的所有cookie  
    var allcookies = document.cookie;         
    //查找名为name的cookie的开始位置  
    name += "=";  
    var pos = allcookies.indexOf(name);      
    //如果找到了具有该名字的cookie，那么提取并使用它的值  
    if (pos != -1){                                             //如果pos值为-1则说明搜索"version="失败  
        var start = pos + name.length;                  //cookie值开始的位置  
        var end = allcookies.indexOf(";",start);        //从cookie值开始的位置起搜索第一个";"的位置,即cookie值结尾的位置  
        if (end == -1) end = allcookies.length;        //如果end值为-1说明cookie列表里只有一个cookie  
        var value = allcookies.substring(start,end);  //提取cookie的值  
        return unescape(value);                           //对它解码        
        }     
    else return "";                                             //搜索失败，返回空字符串  
}  
//删除cookie  
function deleteCookie(name,path){  
    var name = escape(name);  
    var expires = new Date(0);  
    path = path == "" ? "" : ";path=" + path;  
    document.cookie = name + "="+ ";expires=" + expires.toUTCString() + path;  
}